# do all of these in subshells since it's supposed to error out

# first try some invalid patterns
#"$THIS_SH" -c 'echo ${?}' -- this is valid as it's the same as $?
"$THIS_SH" -c 'echo ${:?}'

# then some funky ones
"$THIS_SH" -c 'echo ${#?}'
"$THIS_SH" -c 'echo ${#:?}'

# now some valid ones
"$THIS_SH" -c 'set --; echo _$1'
"$THIS_SH" -c 'set --; echo _${1?}'
"$THIS_SH" -c 'set --; echo _${1:?}'
"$THIS_SH" -c 'set --; echo _${1?message1}'
"$THIS_SH" -c 'set --; echo _${1:?message1}'

"$THIS_SH" -c 'set -- aaaa; echo _$1'
"$THIS_SH" -c 'set -- aaaa; echo _${1?}'
"$THIS_SH" -c 'set -- aaaa; echo _${1:?}'
"$THIS_SH" -c 'set -- aaaa; echo _${1?word}'
"$THIS_SH" -c 'set -- aaaa; echo _${1:?word}'

"$THIS_SH" -c 'unset f; echo _$f'
"$THIS_SH" -c 'unset f; echo _${f?}'
"$THIS_SH" -c 'unset f; echo _${f:?}'
"$THIS_SH" -c 'unset f; echo _${f?message3}'
"$THIS_SH" -c 'unset f; echo _${f:?message3}'

"$THIS_SH" -c 'f=; echo _$f'
"$THIS_SH" -c 'f=; echo _${f?}'
"$THIS_SH" -c 'f=; echo _${f:?}'
"$THIS_SH" -c 'f=; echo _${f?word}'
"$THIS_SH" -c 'f=; echo _${f:?message4}'

"$THIS_SH" -c 'f=fff; echo _$f'
"$THIS_SH" -c 'f=fff; echo _${f?}'
"$THIS_SH" -c 'f=fff; echo _${f:?}'
"$THIS_SH" -c 'f=fff; echo _${f?word}'
"$THIS_SH" -c 'f=fff; echo _${f:?word}'